Base 18

This is a list of numeral systems, that is, writing systems for expressing numbers.

Devanagari 0 १ २ ३ ४ ५ ६ ७ ८ ९

Numeral systems are classified here as to whether they use positional notation (also known as place-value notation), and further categorized by radix or base.

The common names are derived somewhat arbitrarily from a mix of Latin and Greek, in some cases including roots from both languages within a single name.

The common names of the negative base numeral systems are formed using the prefix nega-, giving names such as:

All known numeral systems developed before the Babylonian numerals are non-positional.

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